Primary biliary cirrhosis in the Netherlands - An analysis of associated diseases, cardiovascular risk, and malignancies on the basis of mortality figures

Background/methods: In 1979 death rate registration for primary biliary cirrhosis (PBC) became available in The Netherlands. In the 14-year period 1979-92, 417 persons died of and 179 with PBC. We investigated secondary causes of death using standardized mortality ratios (SMR) (1.0 as reference, P < 0.001 regarded as significant). Results: Median age was 70-74 (35 to > 85) years. Secondary causes of death originated from the circulatory, digestive, and respiratory tracts and malignancies. Younger persons (< 60 years), dying of PBC, more often died with 'toxicity related to immunosuppression' than older persons (P < 0.01). Younger persons (< 60) dying with PBC, more often died of hepatocellular carcinoma (HCC) than older ones (P < 0.05). In patients with PBC the frequency of HCC (SMR, 25.5; P < 0.0001) and diseases of the musculoskeletal system/connective tissue (SMR, 5.1; P < 0.0001) was higher than in the general population. Malignancies in general (SMR, 0.7), pancreatic carcinoma (SMR, 2.5), breast cancer (SMR, 0.1) and diseases of the circulatory system (SMR, 0.8) differed but not significantly (P < 0.05-<0.01). No difference existed in the localization of malignancies in patients dying of as compared with those dying with PBC. Conclusions: Deaths occurred predominantly in the older age classes, with an age-related difference in some associated disorders. Patients with PBC showed an increased risk of HCC and diseases of the musculoskeletal system. Similar studies from different countries are needed.